With constant improvement and development of science and technology, an increasing number of electronic devices have entered thousands of families and enriched people's daily life. To satisfy people's demands for multifunctional, multipurpose and extensible devices, many existing electronic devices may connect to external extension devices, which are called peripherals for short. For example, a computer may further include, apart from its main structure, peripherals such as a keyboard, a mouse, and a speaker. Therefore, for an electronic device, not only system load inside the electronic device needs to be powered, but also a possible peripheral needs to be powered.
An electronic device in the prior art generally uses a fixed power supply mode to supply power to a peripheral. For example, when a mobile phone is charged through a universal serial bus (USB) interface of a computer, a power supply mode that may be provided by the computer to the USB interface is that an output voltage is 5 volts (V), and a maximum output current is 0.5 amperes (A). Therefore, the computer may provide the mobile phone with a maximum power of 2.5 watts (W) through the USB interface.
However, a research and development process finds that a disadvantage in the prior art is that system load power consumption of an electronic device may change at any time. Therefore, when the system load power consumption of the electronic device is low, the electronic device cannot distribute remaining power to a peripheral for use because of being restricted by a fixed mode of peripheral power supply, which results in wasteful power consumption. Therefore, the fixed power supply mode in the prior art results in inflexible power distribution of an electronic device, and cannot implement, with maximum efficiency, power distribution of the electronic devices.